Woochat is a modern chat application available for Android and iOS devices. It allows the user to chat with people, group chatting, send images, videos, voice notes, documents, as well as make video calls and voice calls with other users. It comes with Ionic 3 template (HTML and CSS).
WooChat application is solid with real-time updates when messages are delivered, read and when the recipient responds. It also offers free calls and video calls, lots of stickers and emoticons. You can build chat application with this source code.